Method and apparatus for maintaining tooth and gingival structures with ultrasonic energy



Inventor Lewis Balamuth New York, N.Y.

Appl. No. 722,313

Filed Apr. 18, 1968 Patented Dec. 15, 1970 Assignee Ultrasonic Systems, Inc.

Farmingdaie, N.Y. a corporation of Delaware METHOD AND APPARATUS FOR MAINTAINING TOOTH AND GINGIVAL STRUCTURES WITH Primary Examiner-L. W. Trapp Attorney-Leonard W Suroff ABSTRACT: A method and apparatus in which ultrasonic energy in combination with high-velocity liquid jets provides a system for cleaning of teeth as by the removal of tartar, calculus deposits, stubborn stains, such as are produced by smoking, and simultaneous stimulation of the gingival or gums. The applicator through which the liquid jetstream passes may also be ultrasonically vibrated for engagement with the tooth and gingival structures or the oral cavity to impart thereto microfatigue and ultrasonic impact grinding action for the removal of foreign substances from the teeth and a micromassage of the gingival structure for stimulation thereof.

PATENTEU DEC 1 5 19m sum 2 OF 3 FIG. 2 2/ if? P =1 5L Ill ill Z6! ,,3

l 30 35 I g i H 7 I28 20/ INVENTOR. LEWIS BALAMUTH ATTORNEY PATENTEDUEBI 51976 3354711 10 SHEET 3 0F 3 INVENTOR. LEWIS BALAMUTH ATTORNEY METHOD AND APPARATUS FOR MAINTAINING TOOTH AND GINGIVAL STRUCTURES WITH ULTRASONIC ENERGY BACKGROUND OF THE INVENTION This invention relates generally to the hygienic care of the oral cavity, and more particularly to methods and apparatus utilizing ultrasonic vibratory energy for removal of foreign substances from teeth and the treatment of the gingival tissues 0 No. 3,375,820 of Balamuth and Kuris issued Apr. 2, 1968, for

Methods and Apparatus for Ultrasonic Cleaning of Teeth and referred to as generally the ultrasonic toothbrush". This 'latter invention may be used in conjunction with ultrasonic brush heads as disclosed in U.S. Pat. No. 3,335,443, issued Aug. 15, l967,to Parisi et al.

We are concerned in the present invention with new discoveries by applicant which allow dramatic improvements in the application of ultrasonic energy for periodontal procedures. Before proceeding to the details of the invention, 'let us first review briefly generally known facts of oral hygiene. 2 Let us first look at the oral cavity with its teeth structure and gingival surfaces formed by the gum structure and review the situation as to objectives to be achieved. in the first place, orldinary tooth brushing uses bristles and tooth paste to keep tooth surfaces clean and hopefully, polished and bright (including \vhiteness"). In addition an attempt is made to clean out interproximal, gingival crest, or gumline areas, and other hard-to-get-at areas (without too much success). Finally, Sunder dental teaching, the tooth brusher learns how to stroke 3 the gingival-tooth boundaries so as to provide some gum stimulation. The now successful electric-vibratory, i.e., 60 cycles per second, tooth brushes attempt to meet all the above goals, only with more efficiency and with the aid of outside electrical energy to aid the bristle motions during use. 4 In practice, I believe it is safe to say that the above methods are of limited usefulness, but do not make a basic attack on fundamental factors believed to be involved in periodontal .disease. Let us remember that with advancing life expectancy,

regularbasis which also outpaces the previously-mentioned techniques. Basically, the water massaging device idea is the use of liquid jet forces on an intermittent basis whereby magic bullets" of water go to work to clean teeth and stimulate gums.

Now, none of the methods mentioned so far, do anything to prevent or remove tartar or calculus deposits, or remove stubborn stains such as are produced by smoking. For instance, ultrasonic energy has been called into play here, in order to fill these missing gaps, and this is in part the subject of copending application, Ser. No. 513,491, filed Dec. 15, 1965, now U.S. Pat. No. 3,326,525, of Balamuth et. al. referred to above. Vibrating bristles (with water or water paste or other agents) are introduced to create the unique forces of cavitation, impact grinding, honing and polishing, and soft tissue vibration as a gingival stimulant. In addition, the vibrating bristles also perform the functions of ordinary toothbrushes and electric toothbrushes, as well. Thus, a complete armamentorium is made available to attack the original problem to be solved, namely, adequate home aid to good periodontal and tooth care. The basis has been laid for a sound dental care system, whereby both the dentist and the home appliances combine to make possible a new kind of preventive dentistry.

Table 1 below has been provided to more clearly distinguish the present invention from known systems or techniques of oral hygienic methods and to indicate those particular beneficial actions obtainable with the present invention. In the left hand column various parameters generally considered in evaluating oral hygienic systems are listed. Five systems are listed with the relative ability of each system, relative to the other to attain the best results. As will be seen by a review of the table, systems 1, 2, and 3 are deficient in a number of respects as for example, calculus removal and medicament absorption. System 4, which is the ultrasonic toothbrush, is an improvement over systems 1, 2 and 3, but still does not perform as well as system 5, which is the present invention. In respect to certain parameters, for example, the interproximal cleaning of soft debris by the micropulsed jet of the present invention, produces additional action to dislodge debris as compared to a macropulsed or continuous jet of liquid as in the pulsating jet system. Further, although the ultrasonic toothbrush, of system 4, does a good job of interproximal cleaning, the ability of the individual bristles to penetrate the the loss of teeth and improvement of health is due more to d h between h teeth d permit certain f ei bperiodontal causes than to simple dental caries. It was with this in mind that the water massaging device process or idea -was introduced and it is having considerable success, because it is able to perform interproximal and other cleaning not stances to remain. Further, the microstimulation attainable by the micropulsed jet stream of system 5 permits the micromassage action to take place in areas where the bristles of the ultrasonic toothbrush do not always reach.

possible to ordinary and electric tooth brushing. The water Thus, in accordance with the present invention, the best of massaging device process is generally discussed with reference to U.S. Pat. No. 3,227,156, for Method And Apparatus For Oral Hygiene. In addition, it provides gingival stimulation on a all the oral hygienic parameters are combined to producea new and novel system that is superior to any system available for treatment of the oral cavity.

TABLE 1.TYPE OF SYSTEM Water massaging device or Ultrasonic This Parameter Toothbrush and dentifrice Electric toothbrush equivalent toothbrush invention General removal ofsoft, non-adherent debris. Excellent Excellent Excellent Excellent Excellent. Isnterproximal cleaning of soft debris..... P Poor Very good.. Good 13o. tain Calculus (tartar) .do Gradual Rate 4.

Gum macromassage Moderate 1 =3. Gum micromassage. None None Good. Polishing action Dependent on dentiirice Same as 1 with more rubbing .do Fair.

and rubbing. plus ultrasonic polishing. Whitening action Solely dependent on Same as 1 .do Same as l Chiefly dentifrice. plus sonosonochemical chemical effect. action.

llledicament absorption None None .do Mode etem- Moderate.

OBJECTIVES OF THE INVENTION An object of the present invention is to provide improved methods and apparatus for performing oral hygienic procedures with ultrasonic energy.

Another object of the present invention is to provide novel and improved cleaning techniques for personal oral hygienic care which enables the user to control and obtain significantly better cleaning of teeth.

Another object is to provide new and novel methods and apparatus which are embodied in a device that is completely safe for use by adults and children in the home on a regular basis.

Another object of the present invention is to provide new and novel methods and apparatus for regular personal oral hygienic care which provides excellent cleaning results in the hard to reach interproximal and gumline areas in general, and simultaneous gum stimulation.

Another object of the present invention is to provide improved cleaning techniques for the removal of plaque, tartar, calculus, stubborn stains, interproximal soft debris by a microfatiguing action.

Another object of the present invention is to provide improved techniques for maintaining by micromassage the healthier tonus of the gingival tissue.

Other objects and advantages of this invention will become apparent as the disclosure proceeds.

SUMMARY OF THE INVENTION The present inventor has discovered that although the ultrasonic and the water massaging device methods have, so to speak, laid the foundations for a whole new approach to oral hygiene, an important advance in the art is obtained by achieving a proper combination of the "magic water bullet with ultrasonic energy superimposed thereon or in combination with the ultrasonically vibrating bristles. The inventor has discovered that it is not necessary to have a plurality of bristles in order to achieve the most basic requirements of advanced home dental hygiene, i.e. the removal of plaque, tartar (calculus), stubborn stains, interproximal soft debris, and the stimulation of gingival tissue to healthier tonus. It can be achieved by a single ultrasonically vibrated nozzle, preferably having a continuous or pulsed stream ofliquid passing therethrough.

What is necessary is the kinetic energy of a water stream, such as in a water massaging device system which term is used herein in the generic sense, type of approach provides, combined with an injection of ultrasonic energy over a large enough surface to guarantee presence of significant amounts of cavitational energy as well as the material removing energy of high frequency vibration combined with an artificial or selfinduced slurry. At the same time, if the ultrasonic vibrations are adequately transferred by a microfatiguing action to the plaque and calculus, there is, in addition to the impact grinding kind of material removal, the complementary process of material removal of weakly bonded deposits such as plaque and calculus by means of microfatigue effects. The removal of material in a solid state is generally discussed in applicants US Pat. No. 3,l45,450, for Method Of Ultrasonic Removal Of Material By Fatigue Failure.

BRIEF DESCRIPTION OF THE DRAWINGS Although the characteristic features of this invention will be particularly pointed out in the claims, the invention itself, and the manner in which it may be made and used, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof, wherein like reference numerals refer to like parts throughout the several views and in which:

FIG. I, is a chart indicating the relationship of the various principal factors related to ultrasonic microstimulation for oral hygiene;

FIG. 2, is a perspective view of an ultrasonic jet type oral hygiene unit embodying the present invention;

FIG. 3, is a section through the supply means of FIG. 2 taken along the lines 3-3;

FIGS. 4 and 5, illustrate the applicator means of the present invention in relation to the gingival and tooth structures of a human to obtain a cleaning action, and helpful in explaining the operation of the present invention;

FIG. 6, illustrates the applicator brushing instrument in accordance with the present invention in which the combination of bristles and jet stream is employed;

FIG. 7, is an assembled view, partly in cross section, of the ultrasonic cleaning instrument according to the present invention;

FIG. 8, is a sectional view through the ultrasonic handpiece of FIG. 7, taken along the line 8-8;

FIG. 9, is a sectional view of an applicator in the form of a brush;

FIG. 10, is a sectional view of another form of applicator insert in accordance with the invention; and

FIGS. 11 and 12, illustrate modified applicator constructions.

DETAILED DESCRIPTION OF THE DRAWINGS Referring now to the drawings, FIG. 1 is a chart illustrating the various principal factors of the invention. The microstimulation effect is divided into micromassage stimulation of the gum structure or gingival tissue, and microfatigue effects on tooth structure such as dentin, enamel and fillings. In effect the diagram is an elucidation ofthe invention into separate but simultaneous, or concurrent, actions on hard tissue and soft tissue. Also the acting agencies must be divided into high kinetic energy, low frequency hydrodynamic action of liquids and the action of ultrasonic energy through cavitational and other effects.

These various combinations are attainable by providing the jet stream that has superimposed thereon or imparted thereto the ultrasonic acoustic energy waves to produce the micromassage of the gum structure and the removal offoreign deposits from the tooth structure whether adhered thereto or contained interproximally therewith.

By simultaneously vibrating the applicator in the ultrasonic frequency range and its engagement with the gingival and tooth structures the cleaning action is enhanced by the mere combination of the kinetic energy and ultrasonic vibrations and further by the inducement of cavitational action and impact grinding effects for the removal offoreign substances.

Turning now to FIGS. 2 and 3 there is illustrated an oral hygienic unit 10, which will be described in greater detail hereinafter, and for present purposes it is sufficient to indicate that it includes an instrument or handle means 12 adapted to be held by the user in a conventional manner, having extending from one end thereof supply means 14 which supplies to the instrument means 12 both power and a constant supply of fluid. Applicator means 16 extends from the opposite end of the instrument means 12 and has a passageway extending therethrough and in communication with the supply means 14 to permit the formation of a jet stream of liquid 15 ofa small cross-sectional area, generally in the diametrical range of 0.010 inch to about .070 inch. The fluid generally in the form of a liquid passed through the instrument means 12 and is passed through ultrasonic motor means 18 (see FIG. 7) and has transmitted thereto high frequency mechanical energy, so as to obtain a micropulsing of the stream ofliquid 15 in the ultrasonic frequency range.

The velocity of the jet stream 15 may be controlled by employing pumping means 20 which continuously supplies liquid 21 from the reservoir means 22, either continuously or intermittantly, to create low frequency energy pulses to obtain a macropulsing action. Generating means 24 is provided to convert the current, i.e., 60 cycle, to a frequency in the ultrasonic range, which for purposes of the present invention, "ultrasonic is defined to include the range of approximately 5,000 cycles per second to l,000,000 cycles per second, although the micropulsing of the liquid stream is preferably in the range of approximately 16,000 cycles per second to 40,000 cycles per second.

The oral hygienic unit 10, may be controlled such that the liquid stream may be continuously pumped at a constant rate of flow with the ultrasonic energy transmitted thereto to obtain the micropulsing action, or the liquid stream may be simultaneously pumped to obtain the macropulsing action as well. Which technique is selected will vary with the users condition of his tooth and gingival structures.

To power the unit we have a plug 27 and cord 28 which is in communication with the generator means 24 and pumping means 20. Switching means 26 contains a first switch 30 connected to the generator 24, in a conventional manner, for providing power for energizing the ultrasonic motor contained within the instrument casing 32 of the hand held instrument means 12. The energy from the generator is transmitted to the ultrasonic motor by wires 33 and 34 extending through the flexible conduit 35 ofthe supply means 14.

A second switch 31 is provided to control the pumping action of the liquid supply, such that both the velocity as well as the pumping cycle is controlled. Although reservoir means 22 has been shown in communication with the pumping means 20, it is to be understood that essentially both might be considered the equivalent of a water tap under normal pressure that is controlled as to volume by the conventional control of the faucet, found in the home. But to obtain controlled velocities of the jet it is preferable to provide both reservoir and pumping means. The switch 31 is provided to regulate, in any conventional manner, the pumping means 20 to provide a stream of the fluid 2i through the tube 37 which is contained in the conduit 35, through the ultrasonic motor and then exiting from the applicator means 16 in the direction of arrow 38 in the form of jet stream 15. The applicator means 16 may take various shapes and forms to permit its positionment within the oral cavity. The applicator means 16 may also be coupled to the ultrasonic motor to induce therein ultrasonic energy waves in the direction of double headed arrow 40.

in accordance with the present invention, as is illustrated in FIGS. 4,5 and 6, the applicator means 16 of the hand held instrument is positioned within the oral cavity and the liquid jet stream is directed at either the tooth structure 45 and/or the gingival structure 46. That is, the applicator is inserted in the mouth and positioned adjacent the desired structure to be treated with the liquid jet stream directed in such a such a manner to engage the various portions of the oral cavity. While the treating applicator I6 is being manually moved over the respective tooth and gingival surfaces 48 and 49 respectively, much in the manner in which conventional brushing is performed, except that there may be essentially a spaced relationship between the applicator means as shown in FIGS. 4 and 5, and the engaged structure. The jet stream 15 which is generated by means of the pumping means is of a relatively small cross-sectional area and as the liquid is passed through the supply means 14, and in turn through the instrument means 12, high frequency ultrasonic energy is superimposed on the stream of liquid so as to obtain a micropulsing action thereon. Accordingly, the stream of liquid is then moved to substantially engage the tooth structure 45 or gingival structure 46, within said cavity and it is moved at such a rate, dependent upon the user, to obtain a microstimulating of the engaged structure by transmitting the ultrasonically micropulsed energy waves contained in the jet stream 15 to effect a cleansing action thereof. In this manner a level of hygienic control may be maintained in the oral cavity.

Accordingly, the action obtained by the jet stream in the form of microstimulation may be divided into various subcategories which have been illustrated with respect to FIG. 1.

Particularly, we have the ability due to a microfatiguing action to remove foreign deposits, or substances 50, normally found on teeth which may be generally characterized as stain, plaque, calculus or tartar. Stain and tartar are both adherent deposits on teeth but plaque is somewhat softer and less adherent, such as soft food deposits found between or on the teeth. The ability of the jet stream to engage these hard foreign deposits brings about this microfatiguing action in such a manner such that the bond between the teeth structure and the foreign deposits is weakened by the high frequency energy pulses to the extent that it is broken and the resultant deposits are flushed away by the continuous stream of liquid.

in this manner it has been shown that the ultrasonically continuous or pulsed jet can remove tartar deposits whereas other hygienic systems, hereinabove discussed, have been substantially ineffective. in addition it also removes stain and interproximal deposits in a significantly superior fashion, these improved cleaning results are believed directly related to the ability to continuously supply at an ultrasonic rate micropulsed energy to fatigue the bond between the tooth structure and foreign deposits to obtain the latters removal.

In addition the microstimulation concept also takes another form in its ability to remove tartar deposits by the well-known factors of a liquid combined with a grit, such as toothpaste, or special powder to also assist in removal of tartar and calculus. This is brought about since the jet stream, which is ultrasonically vibrated produces various cavitational action in the area in which it is directed. This is directly related to the high frequency acceleration which further enhances the cleaning action effect and will also assist in the removal of foreign deposits.

As indicated with respect to FIG. 1, we also have what is generally known as an impact grinding effect which materially assists in the removal of the foreign deposits. This effect, discussed in more detail in US. Pat. No. 2,580,716, in which applicant is the inventor, is generally exhibited in the presence ofa cavitating field in addition to material-removing particles. in order to obtain the desired removal effect it is just necessary to bring the vibratory surface of the applicator means 16 into lightly engaged contact with the surface of the structure to be treated and in the presence of the material-removing particles. This may take the form of various dentrifrices which are used to contain certain particles which may be employed in the cavitational action. When the cleaning process is carried out by the use of merely the jet stream, at the proper velocity and pressure, this action will take place by the accumulation of the removed foreign deposits which in turn act as their own grit material and form a basis for the impact grinding process.

Simultaneously with the results obtained by microfatiguing we simultaneously have the action obtained by micromassaging of the gum structure of the organic oral cavity. The jet stream as previously indicated has superimposed thereon ultrasonic vibrations in the range of from 5,000 to l0,000,000 cycles per second and at the same time this stream might be simultaneously pulsed at a defined low frequency to obtain a macropulsing thereof. This low frequency macropulsing is generally in the range of 6 cycles per minute to 26,000 cycles per minute. This permits a combination of effects to be obtained since the macropulsing has certain known beneficial aspects, and the micropulsing has others, which when combined produces results in the maintenance of the condition of the oral cavity not heretofore obtainable.

The micropulsing action produces a micromassage of the treated gingival structure in that the actual energy waves are transmitted to the gingival structure for pervasively penetrating and treating the gingival structure for hygienic control thereof. ln this manner penetration is obtained to a greater depth than available with macropulsing such that ample stimulation and invigoration of the gingival structure, which is most desirable, is obtainable. The actual treatment time, energy level and jet velocity is selected dependent upon the age and condition of the gums of the user, and might be varied so that he might select patterns for specific treatment of his condi- .tion.

Thus, with respect to the treatment of the gingival structure 46 coherent elastic energy waves in the frequency range of 15,000 cycles per second to at least 10,000,000 cycles per second can be applied for treatment of the gingival structure of a biological organism to produce beneficial effects therein. The path of waves may be ofa continuous or pulsed wave pattern which when properly transmitted to the selected portion of the gingival structure in accordance with the present invention, are capable ofinducing micromassage thereof. By employing ultrasonic vibrations it is possible to put considerable quantities of coherent wave energy into biological systems without a significant temperature rise. This means that, looking at any small part of the gingival cells, the passing bf the elastic wave carried by the jet stream causes a rapid oscillation of compression and tension stresses in the structure. This results in a micromassage" which has a beneficial action on the general tonus of the treated cells and under controlled intensities and dosages may be applied to stimulate the circulation and healing of the treated gingival structure.

Essentially the gingival structure is composed of a series of cellular structures containing a fluid medium therebetween. When the oscillation generator is energized the vibratory energy of the ultrasonic motor will create a series of coherent elastic energy waves in the jet stream 15, which appear as wave fronts moving in spaced relation to each other, a wavelength apart. These waves are coupled and transmitted to the gingival structure 46 by means of the elastic medium orjet stream 15. Each moving wave is carried Wstream 151 01 ifansmission to the gingival structure. The spacing between the waves in the gingival structure might be further apart than in the fluid medium of the jet stream because of the difference in the speed of sound in the fluid medium and the gum structure. The wave is purely physical, or mechanical in nature in that each complete wave includes an area of compression in one-half of the wave and a corresponding area of tension or rarefaction in the other half of the wave. Thus, it

may be understood that sound waves in passing through any material create a series of alternate areas of pressure and tension, in which particle motion is extremely slow yet the magnitude of acceleration is high. This means that looking at any small part of the gingival structure, the passing of an elastic .wave causes a rapid oscillation or compression and tension -stresses in the structure.

An underlying principle related to microstimulation, and particularly micromassage, is the fact that mechanical vibrations may be of two general kinds. One being the ordinary gross elastic vibrations of bodies or masses, which belong to what are called coherent vibrations or waves. Coherence means that the vibration of various parts of the wave are in .definite phase relation in time with one another. By contrast,

one has the incoherent or phase-disconnected vibration to be found in solids and liquids and which, in general, comprise what is called the thermal energy ofa body.

'Most ultrasonic vibration of ultra high frequency 1,000,000 cycles per second and higher) are currently widely used for treatment of biological systems including medical therapy for humans. But, due to the high absorption coefficient of high frequency mechanical or elastic waves, the coherent wave energy is rapidly dissipated into thermal energy or heat and the effects produced are mainly due to temperature rise in the hard and soft tissues. In fact, medical ultrasonic therapy as practiced is severely limited by this thennal effect. The dosage of energy must be maintained low enough so that dangerous temperature rises will not occur in vital tissue and organs. In this way the amount of coherent wave energy available for treatment purposes is very small.

To prevent any heat buildup due to thermal effects and therefore allow both the use of higher frequencies in excess of 1,000,000 cycles per second, and higher intensities of coherent elastic waves than heretofore used it has been found that a resting time may be provided during each oscillation, which increases patient comfort.

Applicant has discovered that these resting times may be established by macropulsing the jet stream 15 or the equivalent of such resting times may be realized in another fashion for other kinds of wave energy therapy for both sonic (500 to 16,000 cycles per second), low ultrasonic (16,000 to 600,000 cycles per second), and high ultrasonic (600,000 to 10,000,000 cycles per second and higher) frequency ranges. By placing a vibrator in, say, the tank circuit of an amplifier it is possible to generate bursts or "bunches of vibrations at the resonant frequency of the transducer being used. This is easily accomplished by one skilled in the art as by merely keying the oscillator or electronic means being used to feed energy to the transducer. The point is, that it is readily possible to design the system so as to preselect the length of time of the burst" or "pulse", and also the length of the resting time between bursts.

For example, in superficial types of treatment such as with gums, it is possible to use very high ultrasonic frequencies which will not penetrate very deeply without absorption. The heat generated by a single pulse will be well dissipated if the waiting time for the next pulse is long enough. In this way, the superficial body areas may be treated with special applicators, whereby the chief effects produced are 0 t e coherent wave energy which the pulse contained in the jet stream gives to the tissue. The heat produced by absorption dissipates and here there is no real thermal effect, such as a significant temperature rise in the tissue. For example, consider 60 bunches per second switching to 1 me. waves where the tank Q of the amplifier allows, say complete oscillations to one bunch of resonant vibrations.

The resting time may vary with respect to the treatment time and therefore considerable intensity of wave energy may be contained in a pulse" or burst", which is many times what the tissue could tolerate if the wave treatment were continuous. We have here a kind of magic ultrasonic bullet, which may be directed for a tremendous variety of purposes into the gingival structure. It is to be understood that a variety of applicators may be employed for ultrasonic treatment by my method, and also the ratio of resting time to treatment time may be infinitely varied. For the treatment of given gingival conditions or diseases a frequency and intensity is selected that is compatible with the purpose of the treatment.

In order to understand the unique intercoupling actions involved in this invention, it important to understand the transmission of the energy waves to the gingival tissue for massage and other treatment thereof. In the first place the acoustic impedance of gingival tissue and water are fairly well matched, so that water or waterlike liquids provide an excellent medium by means of which ultrasonic vibrations may be transmitted into tissue from a solid vibrating source.

In order to gage the intercoupling effects still further, let us look at some quantitative data involved. The water massaging device type of action is optimum at about 1,200 pulses per minute or 20 pulses per second. A good water massaging device rate of flow corresponds to about 5 cm.3/sec. Since there are 20 pulses per second, there must be 5/20 or 0.25 gm. ofwater in each pulse. The kinetic energy of each is:

but since the density of water 1 gm/cm, we can say the mass, m, ofa pulse equals the volume of water charged in one pulse. Now if the orifice or jet area is A, then the volume of the pulse is A L, where L is the pulse length. But the pulse length (2) L=vt Where v=velocity of jet r=time for one pulse. Now we have 20 pulses per second as a preferred value, therefore, t=l/20 sec. and so L=vlb 20/ And so the volume ofone pulse is:

Av (3) A L- This is also the mass ofthe pulse in grams for water. So we get: i

(4) KE (1 pulse) A=area of jet nozzle.

A preferred nozzle size is approximately 0.03-in. diameter or 0.076 cm. This gives an A of 0.0045 cm. Also under the condition herein described it is easy to determine that v 1,000 cm./sec. (this is about 33 FPS.

Also:

( K.E. (1 pulse) =52 v. e1-gs=10- joule/pulse And for 20 pulses per second the power input to the gingiva by a typical high speed water massaging device type jet is:

.2 watt pulse (7) I=} c. 41 f? d.

f= frequency of vibration d=amplitude of vibration for d=0.0003 cm. and FpX c.p.s., and pc 1.5 X 10 gm.

sec m2 (8) 1=24 watts For a jet orifice of 0.0045 cm. we get a power imput into the water of the jet pulse of about 0.1 watt. But this is ultrasonic power in a well-matched medium for gingival tissue and so we can expect that the superimposed ultrasonic vibration will convey at least as much microstimulation to gingival tissue for micromassage as the pulsed jet will give macromassgge at the same time.

This calculation does not include the additional micromassage arising from the contact of the smooth end of the vibrating tool or applicator tip against gingival tissue.

Thus, we see that, in a unique way, the combination of the high-s eed jet with the ultrasonically vibrating a m 2; unexpected bon' "tif'g'i'iigival treatment w 1c is not present in either the water massaging device or the ultrasonic toothbrush. Together with the other advantages arising from the combination described in this invention, we have therefore transcended a simply additive combination and have arrived at a truly novel improvement in oral dental hygiene.

Having pointed out the benefits of the micropulsed energy jet, it should be indicated that this jet may now be combined with a direct coupling of the energy which is simultaneously transmitted through the applicator directly to the treated structure. Particularly the apparatus, as hereinafter described in detail, may be so constructed that the instrument is designed that the applicator is simultaneously vibrated in the ultrasonic frequency range as indicated by arrow 40 in FIG. 1. The vibratory component may either be elliptical, longitudinal, torsional, or any combination thereof, and may be transmitted by applicator means directly to the treated surface.

As indicated in FIG. 6, stimudent means 520, which includes a plurality of individual resilient stimudent or bristle members may be coupled to the applicator means 16a for transmission of the mechanical vibrations. The advantages of utilizing the applicator means 16a in substantial engagement with the treated structure, irrespective if it is in the form of a single stimudent which is essentially what is shown in FIG. 2, or a plurality of stimudents as shown in FIG. 6, pertains to the licator tip basic configuration such that the liquid jet 15a of the micropulsed energy waves is contained proximate the filaments such that we obtain the combined effects in a manner to obtain the coupling or transmission of ultrasonic energy to the treated structure in two wave forms, i.e., through substantial direct engagement of a solid member and through a liquid medium directed at a predetermined pressure such that we are able to combine in a single instrument the beneficial effects attributable to the transmission of energy through a substantially solid member, which is in the form of one or more filaments, and of a relatively flexible or compressible member in the form of the liquid jet.

Utilizing the brushing implement of FIG. 6, and as hereinafter discussed with respect to FIG. 9, the brush head is inserted in the mouth of the user and moved across the gingival surfaces to engage both the tooth and gingival structures 45a and 460, with the stimudent or bristle cluster in relatively light contact with the tooth surfaces 480 and the gingival surfaces 490 as well. As the applicator implement 16a is manually moved throughout the mouth the liquid jet stream 15a is continually forced thereagainst to simultaneously engage the desired surface structures. The individual stimudent, or if a plurality of clusters are employed, they assume different positions and permit the removal of foreign deposits that are contained on the tooth surfaces or interproximal as indicated in FIG. 5. Thus, we have in effect a microstimulation which includes a microfatiguing of the foreign substances by transmitting the micropulsed energy waves contained in the stream against the tooth structure for a period of time to fatigue the bond between the tooth structure and the foreign deposits and effect the removal thereof or a simultaneous utilization of impact grinding processes which will assist in this removal. We also have the ability to obtain a micromassaging of the gingival structure by the ultrasonically micropulsed energy stream which pervasively penetrates and treats the structure for the use required. This dual effect obtained by the microstimulation, removes interproximal and gum line foreign substances as well as those adhesions to the surfaces of the teeth as well.

The rate of removal will be dependent upon the accumulation to date and whether or not the patient requires primarily gingival stimulation or removal of materials, in either case he directs the particular jet stream in the direction he so desires.

In order to practice the novel combination or methods discussed hereinabove, in a practical manner to accomplish the desired objectives, it is preferable to provide an ultrasonic motor of low cost, when mass produced. Also, it is important to limit the amount of ultrasonic vibrational energy so that an overzealous user may not wear away the surface or damage the gum structure along with the stubborn stains or calculus. All the requirements cited above may be realized by using a suitable instrument including plastic components which may be designed to be self-limiting vibrational energy transmitters, and at the same time, which are also capable of delivering the continuous pulsating jet stream of liquid to the work site.

In FIGS. 7 through 12, there is shown various embodiments of ultrasonically driven instruments in accordance with the principles of the present invention. As seen best in FIGS. 7 and 8, the instrument means 12 comprises two basic elements, namely an applicator insert 53, and a handle unit 54 for receiving the insert 53 and which together form in part the ultrasonic motor means 18.

The pumping means 20 of the system produces a stream of liquid and the instrument means 12 forms a passageway 72 to transmit the stream of liquid by means of the applicator means 16 which has a continuing passageway therethrough for applying the jet stream 15 to the structure to be treated in the direction of arrow 38. The ultrasonic motor means 18 contained within the instrument means 12 superimposes on the liquid stream mechanical vibrations in the ultrasonic range to form micropulsed energy waves therein. The generator means 24 may be set to provide rest periods by pulsing or modulating the energy waves at a frequency in the ultrasonic range. At the same time the pumping means 20 may be set to provide pulsing at a frequency less than the frequency of said .rhicropulsed energy waves.

The outer casing 32 of the handle unit 54 of the instrument means 12 is generally of a cylindrical element preferably formed of an electrically insulating and fluid-impervious plastic material, which is provided with a central bore 55 exiending axially therethrough. The outer dimensions of the ins trument means 12 is made such as to be comfortably held in the hand without causing fatigue.

3 The handle unit 54 is formed in two sections, a first section which is the outer casing 32 whose exterior surface forms the peripheral surface of the handle, and a second portion 57 including a tubular extension which fits within the member 32, leaving between the members an annular space extending substantially over their entire lengths. Within this annular space is wound a coil 56 of insulated wire for establishing the magnetic field. At the rearward end of the bore in the member 32 is formed a reduced diameter portion 58 sized to receive the applicator insert 53.

' The conduit 35 of the supply means 14 is secured to the end of the instrument, as by applicator insertsupport means 62 having a radial flange 63 secured to the inner bore 54 in any conventional manner, and a rear lip 64 which has the tube 37 snugly fitting thereover. A front lip 65 retains the applicator insert 53 in position.

The applicator insert support means 62 contains a bore 66 to, permit the supply means 14 to be in communication with the instrument means 12 and the passageway 72 extending therethrough. The front lip 62 is of a diameter to snugly fit within the end portion 67 of the applicator insert 53. The resiliency of the material used, such as plastic, in the acoustic element enables the applicator insert 53 to be manually forced olver the front lip 65 by a force which is sufficient to prevent its voluntary release but which a child is capable of applying. Similarly, the applicator insert 53 may be removed from the instrument 12 with the proper amount of force and at the same time provide a fluid tight seal.

The complete assembly for use in the home includes the generating means 24, for example, a transistorized oscillator capable of producing electrical oscillation at a frequency in the ultrasonic range e.g., between 16,000 and 40,000 cycles per second. Various types of such oscillators are known and it is not believed necessary to describe the details herein.

Z-Electrical oscillations and direct current from the source are coupled via the connector 27 (FIG. 1) and the lead 28, to the generator 24 and in turn through the leads 33 and 34 to the coil 56 in axial spaced relation to an acoustic element 70 in the instrument 12 which forms partof the insert 53. There is thus established in the bore 55 of the handle a magnetic field whose magnitude changes at an ultr ic rate. Upon insertion of the applicator insert 53 the magnetosii'l'Ctive portion of the acoustic element 70 is positioned within the magnetic field 'and in well-known manner, provides a mechanical longitudinal vibmtjgp at the frequency of the magnetic field.

.The illustrated embodiment of the applicator insert 53, as shown in partial cross section in FIG. 7, and which forms part of the ultrasonic motor 18, comprises a vibratory transmitting assembly which includes the vibratory or acoustic element 70 -which is preferably made of a nonmetallic material such as plastic or glass etc. but is capable of transmitting and acting as an acoustic element to transmit the high frequency vibratory energy. Secured to the exterior surface of the elongated acoustic element 70 and forming a part thereof, is a plurality 'q'i' spaced-apart strips 71 running actu lly the length of the acoustic element core 70 which as heTeinafter discussed when energized will vibrate and which vibrations may also be coupled to the applicator means 16 such that the latter vibrates ahd is capable of transmitting vibratory energy. In order to vibrate such thin metallic strips, such as nickel from which the strips may be made, it is important that they be bonded to the acoustic element 70. For example, if the acoustic element 70 is of a plastic material in the form of a rod and in the preferred embodiment is illustrated to be hollow having a conduit or instrument passageway 73 extending therethrough, which forms part of the fluid flow passageway 72, and which carries the metallic strips or layers thereon. The metallic material may be bonded to the plastic by several available methods, including electroplating, epoxy bonding and the like. It is of course necessary to supply the nickel coat in such a way that no complete rings or circles of metal are formed. This is to minimize eddy currents. Also it is possible to cut the tube which contains a suitable binder for binding both the support member and nickel together to the underlying plastic. The acoustic element 70 could be glass for sanitary reasons and for high-Q, high efiiciency vibration. But if glass is used definite limitations must be inherent in the driving generator. The sidewall of the acoustic element 70 may also have bonded to it a piezoelectric or magnostrictive pickup element in order to keep the motor automatic in its resonant frequency operation.

In practice the generator may be as small as or l0 watts into the ultrasonic motor, and is preferably in the solid-state type. The forward end 75 of the acoustic element 70 is provided in the conduit 73 with a threaded portion 76 which is adapted to be engageable with the applicator means 16. The applicator means 16 includes an applicator member 80 which at its rear portion 81 is provided with a complimentary threaded portion 82 for engagement with the threads 76. As seen in FIG. 7, the applicator member may include a forward portion 83 which is tapered with respect to the rear portion 81 of the applicator. The applicator member has an applicator passageway or conduit 74 continuing therethrough, and is hollow throughout its entire length to permit the liquid which is being passed through the instrument passageway 73 of the applicator insert 53 to continue in its path to the working or output surface 84 of the applicator means 16. The an gula: relationship between the forward portion 83 and rear portion 81 of the applicator member 80 will be dependent upon the amplitude of vibration of the output surface 84 as well as the configurations of the vibrational pattern desired to be obtained thereat.

Accordingly, the applicator insert 53 which has the fluid passageway 72 extending therethrough is designed such that the acoustic element 70 is positioned in energy transferring relationship to the instrument passageway 73, so that the ul trasonic mechanical vibrations are continuously transmitted to the stream of liquid as it passes therethrough. The applicator means 16 includes the applicator passageway 74 extending therethrough and which is in communication with the instrument passageway 73, such that essentially the passageway 72 is formed by the instrument passageway 73 and the applicator passageway 74. Depending on the design of the ultrasonic system the energy waves may be introduced into the liquid stream in either of said passageways.

Thus, one complete magnetostrictive system would include an acoustic element 70 comprising a properly coated tube member formed of any suitable material capable of supporting vibrations transmitted thereto from the magnetostrictive coating. This will include many metals and hard plastics which are suitable for this purpose. In order to operate most efficiently, the length of the magnetostrictive strips 71 should be equal in length to an integral number of half wavelengths of the material at the frequency of vibration. A suitable material enabling the length of the acoustic element 70 to be maintained within reasonable limits is nickel, but it will be understood that other materials may also be used.

As to a further construction of the applicator insert 53 the acoustic element 70 may also be made from Pyrex glass tubing. On the surface of this tubing a silver metallizing paint is baked on and then nickel plating is placed on the metallized surface. Slotting of the nickel coating is provided by masking the Pyrex tube surface during silver metallizing. This manufacture lends itself to automated mass production. The hollow tube output end of the glass tubing provides a means for attaching a lightweight metal element to receive screw-on plastic or other working tips. The hollow tube also lends itself to through-feed of liquid mediums. The coupling to the casing may be accomplished with -rings or variants of other type mountings. Much simpler. of course, would be permanently attached working tips. in this case the whole insert must be inexpensive enough to be replacable at suitable intervals by buying new ones. The plated glass tube type transducer would lend itself pretty well to this type of approach.

Now, in addition to have the complete system we may include in the handle 54 into which the applicator insert 53 is assembled in addition to the energizing winding, pickup winding in the form of a permanent magnet (not shown) to bias the acoustic strips 71. Now, in addition to this we also have the hydraulic system which includes the reservoir means 22 and a suitable electric pumping means 20, which arrangement was previously discussed with respect to FIGS. 1 and 2.

Front support means for the applicator insert may include a radial flange in the form of an O-ring 85 which prevents the vibrations induced in the applicator insert 53 from being transmitted to the handle portion 54.

FIG. 9, shows applicator means 160 which includes stimudent means 52a in the form of a plurality of bristle clusters 90a in spaced-apart relation and coupled to the applicator member 800 in any conventionai manner, as for example, in accordance with the teachings ofU.S. Pat. No. 3,335,443. The applicator member 80a includes a rear portion 81a having threads 82a for securement to the acoustic element. The forward portion 830 is integral with the output portion 84a from which the bristle clusters 90a extend in a plane substantially normal thereto. The fluid passageway or conduit74a tapers downwardly and terminates in a plurality of apertures 910 through which the liquid flows to form a plurality of spacedapart jets 15a between or in spaced relation to the respective bristle clusters 90a. in this manner as explained with reference to H6. 6 combined effects may be obtained in using a jet and bristles with the jet in spaced-apart relation to the treated structure.

FlG. 10 illustrates another embodiment of the applicator insert 53b that may be used in conjunction with the instrument illustrated in FIG. 7. In the illustrated embodiment, the application insert 53b comprises an elongated magnetostrictive acoustic element 931: formed of a plurality of thin sheets of a magnetostrictive rn terial such as permanickel or permendur, or any other material capable of mechanically elongating when subjected to a magnetic field. in view of the relative dimensions of the magnetostrictive portion 93b, it will be seen that upon insertion in a suitably oriented magnetic field, a significant elongation of the stack will occur. Consequently, upon application thereto of a magnetic field whose magnitude varies, the length of the stack 93b will similarly vary. in accordance with known principles, the magnetostrictive stack 93b is made to be of a length equal to an integral number of half wavelengths in the material at the driving frequency. in this manner, maximum conversion of energy from the magnetic field to mechanical vibration is achieved. As noted hereinabove, other forms of electrical to mechanical transducers, e.g. piezoelectric, ferrites, may also be employed in accordance with the present invention.

Rigidly affixed to one end of the magnetostrictive element 93b, such as by welding, is a connecting member 9412. This member may be formed of any suitable material capable of supporting vibrations transmitted thereto from the magnetostrictive stack and many metals and hard plastics are suitable for this purpose. However, to operate most efficiently, the connecting member 94b should be made equal in length to an integral number of half wavelengths in the material at the frequency of vibration. A suitable material enabling the length of the connecting member 94b to be maintained within reasonable limits is Monel, but it will be understood that other materials may also be used.

Preferably, the connecting member 9412 is formed to produce at its output end 95b an amplification of the longitudinal vibrations applied to its input end by the magnetostrictive member 93b. To effect this function, the member 94b is formed in two sections 96b and 97b of differing diameter. The

transition from the larger to the smaller diameter occurs at a nodal point of vibration, that is, a point along a member wherein longitudinal motion is a minimum. in a uniform diameter element one-half wavelength long, such a node would occur at the quarter wave point, halfway between the ends. By locating the transition point at a nodal plane, proper acoustic impedance transformation takes place and an increased longitudinal amplitude of vibration is obtained at the output end 95b. A more complete discussion of such acoustic impedance transformers may be found in US. Pat. No. Re. 24,033 granted Aug. 29, 1961 to Balamuth and Kuris for Vibratory Machine Tool and Vibratory Abrasion Method."

The applicator member b is rigidly affixed to the forward end b of the connecting member such as by a screwthreaded fastening. By this means, longitudinal vibrations in the connecting body may be transmitted unimpeded to the applicator means 16b and consequently to the stimudent means 52b mounted therein.

Surrounding the magnetostrictive stack 93b and the connecting member 94b is a generally cylindrical casing b formed of a suitable nonmagnetic and fluid impervious material, such as plastic or aluminum. The casing 10% is structurally rigid and spaced from the peripheral surfaces of the stack 93b and connecting member 94b over substantially their entire lengths so as not to be vibrated therewith.

At the connecting member end of the casing 100!) the walls thereof are somewhat thickened to closely engage the peripheral surface of the enlarged portion 96b of the connecting member. At approximately a nodal point of longitudinal motion in the connecting member, an annular insert l0lb of rubber or similar resilient material is secured in the casing and extends therearound to snugly engage a mating depression provided in the outer surface of the connecting member 94b. This serves to firmly support the connecting member within the casing 100b in such a manner that no longitudinal vibration is transmitted to the casing 10%. The insert 10th and the closeness of fit between the casing 10% and the outer surface of the connecting member 94b also provide a fluidtight seal between the casing 100b and the connecting member 94b.

The end of the casing 10% beyond the magnetostrictive portion 93b is thickened at 1021; and provided with an aperture 103i; extending all the way through to receive the front'lip 65b such that the liquid flowing therein enters the passageway 72b, which includes the passageway 73b, which is the space between the stack 93b and the inside of the casing 10Gb. The instrument passageway 7317 continues into the connecting body 94b by means of a conduit including a transverse opening 104b which connects to a horizontal bore 105b which continues to the output end 95b ofthe connecting body.

At its front end, the casing 10% is provided with a smaller diameter shoulder adapted to be engaged by the applicator means 16b which, is generally cylindrical in cross section and provided with the applicator passageway 74b along its length to allow continued flow 0f the jet stream. The applicator insert 53b may also be formed of a plastic material of high resilience, sized so as to firmly engage the reduced diameter shoulder of the casing 1013b. The applicator insert 53b need be removed only when it is desired to replace the applicator means 16b, such as when the stimudent 52b has been worn to a point where it is no longer effective.

The stimudent 5211 may be formed of an annular rubberor plastic member 106b wherein the jet of liquid 15b that exists from the output surface 84b of the support member 80b is in spaced relation to the surface to be treated.

it will be seen that the entire applicator insert 53b is selfcontained and includes only one part subject to wear, i.e. the stimudent 52b in the applicator support member 80b is arranged to be removed without difficulty and replaced with a new unit whenever necessary.

FIG. 11 illustrates a form of the applicator means 16c in which the jet 15c exits from the applicator member 80c at its output surface 84c in spaced relation to a tip 196v thereof by a distance D. This permits the tip 106c to engage the tooth or gum structure and act as a stimudent, while at the same time maintaining the liquid jet force energy spaced therefrom a preselected distance. The fixed spacing between the output surface 84c and the tip 1060 is important in that the user cannot bring the output surface 84c so close to the treated surface as to possibly damp" out the jet stream forces by flooding a discrete area being treated.

FIG. 12 illustrates a form of the applicator means 16d similar to that disclosed in FIG. ll except that stimudent means 52d in the form of individual bristles are provided such that the jet 15d similarly exits from the applicator means 16d in spaced relation to the engaged surface.

From the foregoing, it will be evident that the application of ultrasonic energy by employing micropulsed energy waves to tooth and gingival surfaces is effective to provide significantly improved cleaning action, and, if employed for regular dental care in the home, will result in maintenance of greater dental health than is possible utilizing conventional tooth brushing implements.

While the invention has been described in connection with particular ultrasonic motor and applicator constructions, various other devices and methods of practicing the invention will occur to those skilled in the art. Therefore, it is not desired that the invention be limited to the specific details illustrated and described and it is intended by the appended claims to cover all modifications which fall within the spirit and scope of the invention.

I claim:

1. The method of treating the gingival and tooth structures of the oral cavity for hygienic control thereof, with an applicator adapted to be inserted within the oral cavity, comprising the steps of:

A. inserting said applicator within the oral cavity;

B. generating a stream of liquid of small cross-sectional area;

C. pumping said stream of liquid through said applicator;

D. micropulsing said stream of liquid in said applicator to induce therein energy waves in the ultrasonic frequency range;

E. moving said applicator to direct said stream of liquid within said oral cavity to substantially engage the tooth or gingival structures thereof;

F. microstimulating said engaged structures by transmitting said ultrasonically micropulsed energy waves contained in said stream to effect the treatment thereof, whereby a level of hygienic control may be hygienic control may be maintained in said oral cavity, and

G. pulsing said stream at a frequency below that of said micropulsing frequency to provide doses of mechanical energy at two different frequencies to said treated structure.

2. The method of treating the oral cavity as claimed in claim 1, wherein said micropulsing is obtained by superimposing on said stream of liquid high frequency mechanical vibrations in the frequency range of 5,000 cycles per second to l,000,000 cycles per second.

3. The method of treating the oral cavity, as claimed in claim 2, wherein said frequency of micropulsing is preferably in the range of 16,000 cycles per second to 40,000 cycles per second.

4. The method of treating the oral cavity, as claimed in claim 1, wherein the cross-sectional area of said stream in energy treatment relationship to said structure is in the diametrical range of 0.0 l inch to about 0.070 inch.

5. The method of treating the oral cavity, as claimed in claim I, wherein the frequency of pulsing said stream is in the range of 6 cycles per minute to 26,000 cycles per minute to obtain a macropulsing thereof, whereby said macropulsed energy is transmitted to said selected structure.

6. The method of treating the oral cavity, as claimed in claim I, wherein the frequency of pulsing said stream is in the ultrasonic frequency range.

7. The method of treating the oral cavity, as claimed in claim I whereiw a. said stream of liquid is moved to substantially engage said gingival structure; and

b. said microstimulating includes micromassaging of the cellular structure of said gingival structure by said ultrasonically micropulsed energy waves in said stream pervasively penetrating and treating the accessible inner region of said gingival structure for treatment thereof.

8. The method of treating oral cavity, as claimed in claim 1,

wherein:

a. said stream of liquid is moved to substantially engage said tooth structure and any foreign substances adhered thereto; and

b. said microstimulating includes a microfatiguing of said foreign substances by transmitting said micropulsed energy waves contained in said stream against said tooth structure for a period of time sufficient to fatigue the bond therebetween and effect the removal of said foreign substances therefrom, whereby the tooth structure may be maintained substantially free of foreign substances.

9. The method of treating the oral cavity, as claimed in claim 1, wherein:

a. said stream of liquid is moved to simultaneously engage said tooth and gingival structures; and

b. said microstimulating simultaneously effects a micromassage of said gingival structure and a microfatigue of said tooth structure to remove surface, interproximal and gum line foreign substances therefrom, whereby the hygienic condition of said oral cavity is maintained.

10. The method of treating the gingival and tooth structures of the oral cavity for hygienic control thereof, with an applicator adapted to be inserted within the oral cavity, comprising the steps of:

A. inserting said applicator within the oral cavity;

B. generating a stream of liquid of small cross-sectional area;

C. pumping said stream of liquid through said applicator;

D. micropulsing said stream of liquid in said applicator to induce therein energy waves in the ultrasonic frequency range;

E. moving said applicator to direct said stream of liquid within said oral cavity to substantially engage the tooth or gingival structures thereof;

F. microstimulating said engaged structures by transmitting said ultrasonically micropulsed energy waves contained in said stream to efiect the treatment thereof, whereby a level of hygienic control may be maintained in said oral cavity; and

G. simultaneously transmitting to the selected structure mechanical vibratory energy in the ultrasonic frequency range by means of said applicator inserted within the oral cavity and directly placed in energy transmission relationship to said structure, whereby said microstimulation is obtained by transmitting ultrasonic energy to the treated structure through substantial direct engagement of said applicator and through the liquid medium of said stream applied at a selected velocity.

11. The method of treating the oral cavity, as claimed in claim 10, wherein said applicator includes at least one stimudent element adapted to engage said structure.

12. The method of treating the oral cavity, as claimed in claim 11, wherein said stream of liquid and stimudent are in closely spaced relation to each other for simultaneous engagement of the area of the structure under treatment.

13. The method of treating the gingival and tooth structures for therapeutic purposes with an applicator adapted to be inserted within the oral cavity, comprising the steps of:

A. inserting said applicator within the oral cavity;

8. vibrating said applicator in the ultrasonic frequency range for generating elastic energy waves;

C. pumping a jet of liquid through said applicator;

D. micropulsing said jet of liquid to induce therein elastic energv waves in the ultrasonic frequency range;

E. selecting said ultrasonic frequency ranges for said applicator and jet, compatible with the portion of the structure to be treated;

F. microstimulating the portion of the engaged structure being treated by transmitting the combined elastic energy waves of said applicator and jet stream thereto, and by manually moving said applicator across the surfaces of the structures to be treated; and

G. pulsing said jet in a preselected pattern of pulses at spaced intervals of time to provide successive doses of said elastic energy waves to said treated structure.

14. The method of treating the gingival and tooth structures, as claimed in claim 13, further including the step of maintaining said jet exiting from, said applicator, in spaced relation to said treated structure.

15. The method of treating the gingival and tooth structures, as claimed in claim 13, wherein said jet ofliquid and applicator are vibrated at substantially the same frequency.

16. The method of treating the gingival and tooth structures, as claimed in claim 13, wherein said elastic energy waves of said micropulsed jet of liquid is induced therein as said jet is pumped through said applicator.

17. The method of treating the gingival and tooth structures, as claimed in claim 13, wherein said microstimulating of said gum structure induces a micromassage of the cellular structure thereof.

18. The method of treating the gingival and tooth structures, as claimed in claim 13, wherein said microstimulating of said tooth structure induces a microfatigue of any foreign substances contained thereon to effect the removal thereof.

19. A system for use in treating the tooth and gingival structures for personal dental hygienic care, comprising:

A. means for producing a stream of liquid;

B. means for forming a passageway to transmit said stream of liquid, said means for forming a passageway includes a hand held instrument containing said passageway through which said stream of liquid passes;

C. means for superimposing on said stream of liquid mechanical vibrations in the ultrasonic range to form micropulsed energy waves therein, for treatment of said structures, said means of superimposing on said stream said micropulsed energy waves, includes motor means contained within said hand-held instrument for converting electrical energy into mechanical vibrations at an ultrasonic rate for vibrating an acoustic element contained therein, said acoustic element positioned in energy transferring relationship to said passageway, wherein said ultrasonic mechanical vibrations are transmitted to said stream of liquid as it passes therethrough,

D. means in communication with said passageway for applying said stream of liquid to said structures, said means for applying said stream of liquid to said structures, includes applicator means adapted to be moved freely relative to the tooth and gingival structures and having an applicator passageway extending therethrough and terminating at an output surface, said applicator passageway in communication with said instrument passageway, whereby said micropulsed liquid stream may pass therethrough for engagement with said structures; and

E. means for coupling said applicator means to said motor means to vibrate said applicator means at an ultrasonic rate, whereby said mechanical vibrations of said applicator means is adapted to be transmitted to said treated structures.

20. A system as in claim 19, further including means for pulsing said energy waves to obtain a rest period between successive doses of energy.

21. A system as in claim 20, wherein said rest period is obtained by pulsing said stream at a frequency less than the frequency of said micropulsed energy waves.

22. A system as in claim 20, wherein said rest period is obtained by pulsing said energy waves at a frequency in the ultrasonic range.

23. A system as claimed in claim 19, wherein said motor means includes:

a. coil means in axial spaced relation to said acoustic ele ment for creating an alternating magnetic field at the frequency of alternating current signals applied thereto; b. said acoustic element including an elongated tubular member forming said passageway extending therethrough; and c. a plurality of spaced-apart strips of magnetostrictive material extending axially along said tubular member and secured thereto, said strips being disposed in said magnetic field, whereby upon application of alternating current signals to said coil said elongated member mechanically vibrates in a longitudinal direction and vibrations are induced in said liquid stream within said passageway. 24. A system as claimed in claim 23, wherein said acoustic element and said coupled applicator means are adapted to be removably secured to said motor means for interchangability therewith.

25. A system as claimed in claim 19, wherein:

a. said applicator passageway terminates in at least one aperture on said output surface; and

b. stimudent means extending from said output surface in spaced relation to said aperture, whereby treatment may be obtained by the combined effects of said liquid stream and vibrated stimudent means.

26. A system as claimed in claim 25, wherein:

a. said passageway terminates in a plurality of spaced-apart apertures through which said micropulsed liquid flows; and

b. said stimudent means includes a plurality of bristle clusters with said respective apertures in spaced relation thereto.

27. A system for use in treating the tooth and gingival strucmicropulsed energy waves therein, for treatment of said structures, said means of superimposing on said stream said micropulsed energy waves, includes motor means contained within said hand-held instrument for converting electrical energy into mechanical vibrations at an ultrasonic rate for vibrating an acoustic element contained therein, said acoustic element positioned in energy transferring relationship to said passageway, wherein said ultrasonic mechanical vibrations are transmitted to said stream of liquid as it passes therethrough; and

D. means in communication with said passageway for applying said stream of liquid to said structures, said means for applying said stream of liquid to said structures, includes applicator means having an applicator passageway extending therethrough and terminating at an output surface, said applicator passageway in communication with said instrument passageway, whereby said micropulsed liquid stream may pass therethrough for engagement with said structures, said applicator means includes a tip portion in spaced relation to said output surface, wherein said stream is maintained in spaced relation to the treated structure.

28. A system as claimed in claim 19, wherein:

a. said acoustic element includes a magnetostrictive portion;

b. a connecting member coupling said magnetostrictive portion to said applicator means, said connecting member including a conduit in communication with said instrument and applicator passageways; and

c. a casing in spaced relation to said magnetostrictive portion and sealed at one end in surrounding relation to said connecting member and open at its opposite end in communication with said means producing said stream of liquid, the spacing between said casing and acoustic element forming said instrument passageway.

29. A system for use in treating the tooth and gingival structures of the oral cavity for personal dental hygienic care, comprising:

A. reservoir means for retaining a supply of liquid;

B. pumping means in communication with said reservoir means for continuously supplying liquid therefrom, said pumping means adapted to form a jet of liquid;

C. instrument means adapted to be hand-held by the user and in communication with said pumping means for receiving said jet stream which is adapted to pass through an instrument passageway extending therethrough;

D. motor means contained within said instrument means for converting electrical energy into mechanical vibrations at an ultrasonic rate, said motor means in energy transmission relationship to said jet stream within said instrument passageway to impart thereto micropulsed energy waves for treatment of said structures; and

E. applicator means extending from one end of said instrument means for movement freely within the oral cavity. and having an applicator passageway extending therethrough in communication with said instrument passageway, and terminating in a single nozzle, said jet stream passing through said applicator and forming a single nozzle jet stream for transmitting said energy waves to said treated structures. ltrasonic rates, whereby said mechanical vibrations of said applicator means is adapted to be transmitted to said treated structure.

30. A system as in claim 29, further including means for coupling said applicator means to said motor means to vibrate said applicator means at ultrasonic rates, whereby said mechanical vibrations of said applicator means is adapted to be transmitted to said treated structures.

31. A system as in claim 29, wherein said pumping means is adapted to pulse said jet stream within a defined frequency range. 

